1. Field of the Invention
The present general inventive concept relates to an image forming apparatus, and more particularly, to an image forming apparatus that can effectively sense and release a printing medium jam on a feed path, and a method of sensing a printing medium jam in the image forming apparatus.
2. Description of the Related Art
Conventional image forming apparatuses have a charging process that charges a surface of a photoconductor to an electric potential, an exposing process that irradiates light onto the surface of the photoconductor from a light scanning unit, such as a laser scanning unit, and forms an electrostatic latent image on the surface of the photoconductor, a developing process that develops the electrostatic latent image into a visible toner image by supplying toner developing material onto the electrostatic latent image, a paper feeding process that feeds printing paper along a feed path after feeding the printing paper from a paper feeding cassette, a transfer process that transfers the toner image from the photoconductor onto the printing paper, a fusing process that fuses the toner image onto the printing paper by applying a high temperature and pressure, and a feed-out process that feeds the printing paper out of the image forming apparatus.
During the fusing process, the printing paper becomes flexible due to the high temperature and pressure for fusing the toner image. This factor or some other factors can contribute to causing the printing paper to become entangled around a heat roller when the printing paper is fed through a fuser nip, which causes a printing paper jam or “accordion jam”.
In order to sense the printing paper jam, an out-feed sensor is usually located between the fuser nip and an out-feed roller. However, the out-feed sensor is expensive and therefore increases a production cost, and when the out-feed sensor malfunctions, the printing paper jam may become serious, possibly making the removal of jammed paper difficult and damaging peripheral elements. Therefore, there is a need to prevent serious printing paper jams and to minimize a production cost generated as a result of attempts to address the printing paper jam.